Fluidic Membrane Accelerating the Kinetics of Photoactivatable Hybridization Chain Reaction for Accurate Imaging of Tumor- Derived Exosomes

Slow intermolecular collisions and always active responses compromise the amplification efficiency and response accuracy of nonenzymatic hybridization chain reaction (HCR). In this study, a photoactivatable membrane-oriented HCR (MOHCR) system was rationally designed by binding a photocleavable initiator probe onto a target protein and then anchoring cholesterol-modified hairpin-structure fuel probes. When irradiated, the bound initiator probe was photoactivated and initiated self-assembly to generate activatable and amplified imaging. In a proof-of-concept assay, breast-cancer-derived exosomes were imaged based on the surface protein epithelial cell adhesion molecule (EpCAM). Photoactivatable responses provided precise spatiotemporal control of the MOHCR, and fluidic membranes enabled accelerated reaction kinetics. Our MOHCR system demonstrated high efficiency and accuracy in differentiating between plasma samples from breast cancer patients and healthy donors.

Automated summary

In this study, a photoactivatable membrane-oriented HCR system was designed to achieve amplification imaging through self-assembly initiated by a photoactivated initiator probe. Based on imaging of specific surface proteins, our system demonstrated high efficiency and accuracy in differentiating between plasma samples from breast cancer patients and healthy donors.